v2.4.0.8

Investments - Fair Value and Unrealized Losses (Details) (USD $) In Thousands, unless otherwise specified | Sep. 30, 2013 securities | Dec. 31, 2012 securities
--- | --- | ---
Fair value |  |
Less than 12 months, Fair Value | $ 982,363 | $ 253,333
12 Months or More, Fair value | 162,774 | 143,853
Total, Fair value | 1,145,137 | 397,186
Unrealized losses |  |
Less than 12 months, Unrealized losses | (45,392) | (2,571)
12 Months or More, Unrealized losses | (3,152) | (5,445)
Total, Unrealized losses | (48,544) | (8,016)
Number of securities in loss position (in securities) | 109 | 32
12 Months or More, number of securities (in securities) | 11 | 9
U.S. agency bonds – mortgage-backed [Member] |  |
Fair value |  |
Less than 12 Months, Fair value | 601,779 | 158,591
12 Months or More, Fair value | 39,548 | 0
Total, Fair value | 641,327 | 158,591
Unrealized losses |  |
Less than 12 Months, Unrealized losses | (23,199) | (1,473)
12 Months or More, Unrealized losses | (1,031) | 0
Total, Unrealized losses | (24,230) | (1,473)
Non-U.S. government bonds [Member] |  |
Fair value |  |
Less than 12 Months, Fair value | 10,234 |
12 Months or More, Fair value | 0 |
Total, Fair value | 10,234 |
Unrealized losses |  |
Less than 12 Months, Unrealized losses | (444) |
12 Months or More, Unrealized losses | 0 |
Total, Unrealized losses | (444) |
Other mortgage-backed bonds [Member] |  |
Fair value |  |
Less than 12 Months, Fair value | 13,152 |
12 Months or More, Fair value | 0 |
Total, Fair value | 13,152 |
Unrealized losses |  |
Less than 12 Months, Unrealized losses | (59) |
12 Months or More, Unrealized losses | 0 |
Total, Unrealized losses | (59) |
Corporate bonds [Member] |  |
Fair value |  |
Less than 12 Months, Fair value | 354,698 | 94,742
12 Months or More, Fair value | 123,226 | 141,842
Total, Fair value | 477,924 | 236,584
Unrealized losses |  |
Less than 12 Months, Unrealized losses | (21,689) | (1,098)
12 Months or More, Unrealized losses | (2,121) | (5,394)
Total, Unrealized losses | (23,810) | (6,492)
Municipal bonds [Member] |  |
Fair value |  |
Less than 12 Months, Fair value | 2,500 |
12 Months or More, Fair value | 0 |
Total, Fair value | 2,500 |
Unrealized losses |  |
Less than 12 Months, Unrealized losses | (1) |
12 Months or More, Unrealized losses | 0 |
Total, Unrealized losses | (1) |
Available-for-sale securities [Member] |  |
Fair value |  |
Less than 12 Months, Fair value |  | 253,333
12 Months or More, Fair value |  | 141,842
Total, Fair value |  | 395,175
Unrealized losses |  |
Less than 12 Months, Unrealized losses |  | (2,571)
12 Months or More, Unrealized losses |  | (5,394)
Total, Unrealized losses |  | (7,965)
Other investments [Member] |  |
Fair value |  |
Less than 12 months, Fair Value |  | 0
12 Months or More, Fair value |  | 2,011
Total, Fair value |  | 2,011
Unrealized losses |  |
Less than 12 months, Unrealized losses |  | 0
12 Months or More, Unrealized losses |  | (51)
Total, Unrealized losses |  | $ (51)

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